# std::move_iterator<Iter>::operator[]

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< cpp‎ | iterator‎ | move iterator

/* unspecified */ operator[]( difference_type n ) const; |  | (constexpr since C++17) (until C++20)
constexpr reference operator[]( difference_type n ) const; |  | (since C++20)

Returns a reference to the element at specified relative location.

### Parameters

n | - | position relative to current location

### Return value

std::move(`current`﻿[n])(until C++20)ranges::iter_move(`current``` + n)(since C++20)

### Notes

The return type is unspecified because the return type of the underlying iterator's operator[] is also unspecified (see LegacyRandomAccessIterator). | (until C++20)

### Example

Run this code

    #include <cstddef>
    #include <iomanip>
    #include <iostream>
    #include <iterator>
    #include <list>
    #include <string>
    #include <vector>

    void print(auto rem, const auto& v)
    {
        for (std::cout << rem; const auto& e : v)
            std::cout << std::quoted(e) << ' ';
        std::cout << '\n';
    }

    int main()
    {
        std::vector<std::string> p{"alpha", "beta", "gamma", "delta"}, q;
        print("1) p: ", p);

        std::move_iterator it{p.begin()};

        for (std::size_t t{}; t != p.size(); ++t)
            q.emplace_back(it[t]);

        print("2) p: ", p);
        print("3) q: ", q);

        std::list l{1, 2, 3};
        std::move_iterator it2{l.begin()};
    //  it2[1] = 13; // Compilation error: the underlying iterator
                     // does not model the random access iterator
    //  *it2 = 999;  // Compilation error: using rvalue as lvalue
    }

Possible output:

    1) p: "alpha" "beta" "gamma" "delta"
    2) p: "" "" "" ""
    3) q: "alpha" "beta" "gamma" "delta"

### See also

operator*operator-> (C++11)(C++11)(deprecated in C++20) | accesses the pointed-to element (public member function)

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